The Giants are building a bullpen out of injured relievers, and it just might work

Jason Foley won't be healthy until midseason but he could help the team late this season and next season. Ken Blaze / USA Today

The best possible way to build a great bullpen is to develop eight pitchers, with seven of them throwing absolute smoke from a variety of arm angles. The eighth pitcher should throw 55 miles per hour from between his legs.

The second-best way to build a bullpen is to throw reliever-shaped noodles at the wall and see how many of them stick.

The third-best way is a combination of the first two.

This concludes our look at the only three ways to build a great bullpen. Because you can't buy one. You can't trade for one. I mean, you can do either of those things, but the results would resemble the Elon-playing-poker story. Just because you used your resources to arrive at the correct result once, that doesn't mean it was smart to use a bad process.

The Giants would rather spend their money on a starting pitcher, another hitter or both, so they're collecting low-cost bullpen options. Don't think of them all as "fliers" or "raffle tickets" -- two of them got guaranteed deals. You will see some, if not all, of these pitchers on the active roster this year. Here's what to expect from them:

Apologies for the delay on this article, but I stayed up all night creating a video of Santos throwing a pitch in a Giants uniform, just to show you what it looked like:

Yessir, no AI for me. I spent hours in Adobe Premiere making this, and ...

Fine, that's from 2021, when Santos was a rookie. It's hard to remember now, but he wasn't thought of much differently than Camilo Doval. Santos was an "if he could just harness his stuff" champion.

The Giants got tired of waiting, though. They traded Santos to the White Sox after the 2022 season, and in 2023, he put up an excellent season for them, with a 3.39 ERA (2.65 FIP) in 60 appearances. His walk rate dropped dramatically, and he looked like a high-leverage arm that the Giants regretted losing.

Then Santos was traded to the Mariners for another high-octane pitcher the Giants let go (Prelander Berroa), but he was injured for most of his Mariners career, with a variety of arm and knee problems. After arthroscopic knee surgery in April, now he's back on the Giants on a minor-league deal, and he's still just 26 years old and in possession of a live fastball.

There's a twist, though. Santos' four-seamer was never a big bat-missing pitch, even when it was in the triple digits. So White Sox (and former Giants) executive Brian Bannister told him to ditch the four-seamer in favor of a sinker. Here's what it looked like in his only successful major-league season:

That's a spicy sinker. The velocity wasn't quite back when he appeared late last season with the Mariners, which is understandable for a pitcher building back strength, but that's a pitch that shouldn't need 99 mph to work.

More than anything, though, Santos is a great example of what the Giants are trying to do with the bullpen. They're getting guys who have had major-league success, but haven't had it in a year or two because of injuries. Keep in mind that they're getting a much different Santos than the one they traded away, though. Possibly for the better.

The best way to explain Hentges (and the concept of building a bullpen in general) is that if he were a free agent after the 2022 season, he would have made $30 million, easy. If he were a free agent after the 2023 season, he might not have made as much guaranteed money, but he still would have netted a multi-year deal.

However, he missed most of the 2024 season following shoulder surgery, and during his recovery, he also injured his knee, which cost him the 2025 season. I think there should be a "throws harder than 95" union, where the relievers who get those $30 million contracts kick a little down to the pitchers who didn't get the same fortuitous timing with their free agency. Get them a gift card, at least.

When he's healthy, Hentges is a tall, power-minded left-hander who can get a lot of swings and misses. He's also not someone who needs to be protected against right-handed batters, as you can see from this curve to Cal Raleigh:

He had platoon splits in 2022, but they were the happy kind, where he absolutely dominated lefties but was merely very good against righties. In 2023, he had reverse splits. In a best-case scenario, this is the kind of left-hander who can close.

The big problem with this kind of free-agent strategy, though, is that you're definitely further removed from that best-case scenario. The Guardians were hoping for a healthy Hentges for last season's postseason push, but his knee didn't cooperate.

Still, the Giants aren't paying him for his performance in 2025. They're paying for it in 2026 -- on a one-year, $1.4 million deal -- and they're hoping for a return to form. The best part might be that if it works, he's still arbitration eligible next year, too. So instead of thinking of this as a one-year deal, think of it as a one-year deal with a ludicrously cheap team option.

Combined with his overall stuff and profile, that contract situation makes this my favorite move of the offseason. Other players will have more impact, obviously, but the Giants weren't going to overhaul the bullpen without a couple of pitchers like this. This might be the best one who was available to them.

This isn't the first time the Giants have given a major-league contract to a pitcher who missed the previous season and wasn't expected back until the middle of the following season. John Brebbia took this path, and while he didn't give the Giants much in 2021, he led them in appearances in 2022.

Foley missed last season with a shoulder injury, and he isn't expected back until midseason. Unlike Brebbia, though, Foley isn't a high-strikeout guy. The right-hander can throw his sinker 99 mph, but he uses it to get ground balls, not swings and misses. He nibbles more against left-handers, too, so he's not without platoon concerns. He was effective with the Tigers before his injury, but he wasn't superlative.

This would suggest a bullpen arm that the Giants would love to tinker with. He has enough raw talent in his arm that One Weird Trick could turn him into a bullpen monster, whether it's a different pitch shape, a different usage pattern or improved command, but you can use that description on a few dozen pitchers in any given offseason.

Except the Giants also gave Foley a major-league contract, even though he won't be fully healed from his shoulder surgery until the middle of the season. It's tempting to look at this as the offseason equivalent to a trade-deadline acquisition -- banking an extra arm they're almost certainly going to need in July -- and that might end up being how it plays out. But the Brebbia path is instructive here, as Foley is under team control for the next two seasons.

This might be a move that sets the Giants up for success in 2027 more than next season, but they'll also be happy with whatever he can add in the summer. That was the plan with Brebbia, most likely, and it wasn't disastrous when he needed that extra year to be 100 percent.

So what's the Giants' bullpen-building strategy thus far? Acquire several recently injured pitchers with a skill (or skill set) that's hard to find and expensive to acquire. Put your organizational resources behind their ability to recapture their past success, and hope like heck that a couple of them do.

It's not a strategy that should make you feel comfortable, but bullpens don't exist to make you comfortable. They exist to haunt your waking hours and crawl into your subconscious while you sleep, pulling out wires and breaking windows. There is no bullpen-building strategy that makes you feel comfortable, other than having so many great pitching prospects that you can't fit them all into the rotation.

Until then, here's what you get with a team looking to upgrade other positions first. It makes perfect sense, even if there's an unbelievably wide range of outcomes. People forget that "bullpen" is a portmanteau from two Latin words that mean "unbelievably wide range" and "outcomes."